Abstract
We have correlated the ‘bedding-in’ response (the high femoral head penetration seen in the first two years after operation) with changes in offset and leg length from opposite normal hip.
Fifteen patients with serial x-rays taken in the first 5 years after operation had measurement of PE wear, femoral offset and leg length change from the opposite normal hip.
There was a weak correlation between increasing the leg length and increasing the offset during operation and increased femoral head penetration (‘bedding-in’) seen during the first two years after the operation. There was no correlation between offset and PE wear after two years in the PCA prosthesis.
Increased tissue tension in the first two years caused an increase in femoral head penetration. This effect is not continued beyond two years.
The abstracts were prepared by Jean-Claude Theis. Correspondence should be addressed to him at Department of Orthopaedic Surgery, Dunedin Hospital, Private Bag 1921, Dunedin, New Zealand.
